US 2004/0096312 A1 shows a turbine having the features of the preamble of claim 1. The stator blade carrier in this case possesses an annular web, in the end faces of which are arranged undercut ring ducts which in each case receive a seal cooperating sealingly with a confronting ring-shaped radial surface of the turbine housing. In this case, the seals, held immovably on the stator blade carrier in the axial direction of the rotor, also serve for fixing the stator blade carrier axially.
DE 732 470 shows a turbine in which the stator blade carrier is sealed off with respect to the housing by means of two seals, a seal arranged fixed on the housing cooperating with the stator blade carrier in the manner of an axial bearing, and a seal arranged in a circumferential groove on the stator blade carrier shutting off a ring-shaped radial gap between the stator blade carrier and housing.
U.S. Pat. No. 1,625,541 shows a turbine, in which the stator blade carrier engages positively by means of an outer-circumferential annular web into an inner-circumferential annular groove on the turbine housing, a gap which remains between one end face of the annular web and the confronting flank of the annular groove being closed off by means of a seal which is arranged in an annular groove on the abovementioned end face of the annular web.
JP 55-52501 illustrates a turbine housing and a stator blade carrier which has on its outer circumference a radially outwardly open annular groove, into which an annular web arranged on the housing engages with axial play. This play is eliminated by means of an annular spring which is tension-mounted axially between a flank of the annular groove of a stator blade carrier and the confronting end face of the housing-side annular web and moreover assumes the function of a seal.
According to DE 926 071, in a steam or gas turbine with a cylindrical stator blade carrier inserted into the turbine housing, there is provision whereby an annular part is arranged on the outer circumference of the stator blade carrier and has an outer circumferential groove, into which an inner-circumferential annular web of the housing engages positively, seals being arranged between the groove-side flanks and the confronting end faces of the annular web.
EP 1 744 017 A1 shows a combined steam turbine with a high-pressure module and with a medium-pressure module in a housing common to both modules, the housing having an inner housing with two expansion sections and an outer housing surrounding the inner housing. In this case, a seal arrangement is provided between the inner and outer housing at the interface between the two modules.
EP 1 445 519 A1 relates to a high-pressure sealing ring for steam turbines, there being provided for sealing off an interspace from an outside space between a first sealing partner and a second sealing partner a tube-like sealing ring which has two legs in cross section, one leg bearing against the first sealing partner and the other leg against the second sealing partner, and the sealing ring being firmly clamped to the second sealing partner via a holding device. One leg of the sealing ring lies sealingly on an end face extended in a radial plane, while the other leg of the sealing ring bears against an inner circumferential surface.
JP 10-169408 shows, on the one hand, sealing rings with a U-shaped cross section between radial surfaces confronting one another and, on the other hand, a sealing ring between an inner circumferential surface and an outer circumferential surface coaxial thereto.
JP 58185903 shows an annular web which is arranged on an inner circumferential surface and which engages into a circumferential groove on an outer circumferential surface, a seal being arranged between a flank of the circumferential groove and the confronting end face of an annular web.
U.S. Pat. No. 5,676,521 discloses a turbine for a power plant, having a stator which has a housing and in the housing two stator blade carriers with a plurality of rows of stator blades. Furthermore, the turbine comprises a rotor which has a rotor shaft with a plurality of rows of moving blades. Moreover, a sealing device is provided in each case for the respective stator blade carrier, said sealing device sealing the respective stator blade carrier axially with respect to the housing and at the same time separating two regions of different pressure from one another.
An effective axial seal inside the housing is especially important in order to avoid or reduce leakage flows. Such leakage flows may possess, particularly in steam turbines, comparatively pronounced abrasive effects which may lead in time to considerable damage to the respective sealing device or the respective stator blade carrier or housing. Such damage then has to be repaired at very high outlay. Moreover, leakage trails lead to significant losses of efficiency in the turbine.